Banca de QUALIFICAÇÃO: ALICE MARIANA SOUZA DE ALMEIDA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ALICE MARIANA SOUZA DE ALMEIDA
DATE: 25/07/2025
TIME: 14:00
LOCAL: Departamento de Química - Auditório de Química
TITLE:

INSECTICIDAL AND ACARICIDAL ACTIVITY OF NANOEMULSIONS FORMULATED FROM ESSENTIAL OILS OF Piper SPECIES ON Plutella xylostella AND Tetranychus urticae

KEY WORDS:

Piper; Essential oil; nanoemulsions; two-spotted spider mite.

PAGES: 141
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Química dos Produtos Naturais
SUMMARY:

Nanoemulsions formulated with essential oils provide a solution to the high volatility and rapid manipulation of oils in agricultural applications. Thus, the objective of this study is to formulate nanoemulsions of Piper marginatum and Piper aduncum, evaluate their physical characteristics and their acaricidal and insecticidal potential against Tetranychus urticae and Plutella xylostella. The essential oils were analyzed by Gas Chromatography coupled to Mass Spectrometry and presented a chemical composition with a variety of terpenic and phenylpropanoid compounds, with (Z)-isoelemicin (21.79%) being the major compound of P. marginatum and Dill apiol (74.73%) the major compound of P. aduncum. The nanoemulsions were formulated by the low-energy method, with different proportions of essential oil, surfactants and water. The nanoemulsions were analyzed by Photon Correlation Spectroscopy, where particle sizes, polydispersity index and zeta potential were obtained. The PM3, PM4 and PA4 nanoemulsions presented particle sizes of 35.24 nm, 81.85 nm and 56.58 nm, respectively. All zeta potential values were below -30 mV. The nanoemulsions were subjected to shelf tests for one year and forced degradation under heating, freezing, acid or base hydrolysis and oxidation conditions. The acaricidal activity against T. urticae of PM3, PM4 and PA4 in the residual toxicity bioassay showed LC50 of 10.55 µL.mL-1, 31.34 µL.mL-1 and 13.10 µL.mL-1, respectively. In addition, all nanoemulsions showed repellent potential when compared to the positive control Azamax®, as well as acaricidal activity in the semi-field test, surpassing the effects of the essential oils tested alone. All products showed low cytotoxicity in the bioassay against Artemia salina.

COMMITTEE MEMBERS:
Presidente - MARCILIO MARTINS DE MORAES
Interno - CLAUDIO AUGUSTO GOMES DA CAMARA
Interno - JOAO RUFINO DE FREITAS FILHO
Externa à Instituição - CAROLINA ALVES DE ARAUJO - UFRPE
Externo à Instituição - MARCILIO WAGNER FONTES SILVA - UFRPE
Externo à Instituição - RODOLFO RODRIGUES DA SILVA - UFRPE